docs: def user(self, username=None):
          """gets the user's content.  If None is passed, the current user is
          used.
  
          Input:
           username - name of the login for a given user on a site.
          """
          if username is None:
              username = self.__getUsername()
  
          url = "%s/%s" % (self.root, username)
          return User(url=url,
                      securityHandler=self._securityHandler,
                      proxy_url=self._proxy_url,
                      proxy_port=self._proxy_port,
                      initalize=True)